Answer:
The answer is below
Step-by-step explanation:
A linear function graph can be represented by:
y = mx + b; where m is the slope and b is the y intercept, x is the independent variable and y is the dependent variable.
a) From the graph we can see the graph passes through the point (0, 100) and (20, 400). Hence we can use the following formula to find the equation:

b) An example of real life linear function is the energy consumed per day in kWh. Let us assume 5 kWh is consumed each day by the person. Since the independent variable is the days, it would be on the x axis, while the dependent variable (energy consumed) would be on the y axis.
ANSWER

EXPLANATION
The given expression is

We regroup the numerical parts to get;

Now let us simplify the negative numbers.

We now subtract 19 from 42 to get;

We can't simplify further
Hence the simplest form is:

Y = 12x......y = 12(4).....y = 48.....so she pays $ 48 for the old brand when buying 4 boxes
y = 8x...y = 8(4)......y = 32...so she pays $ 32 for the brand she changed to, when buying 4 boxes
so the super saving brand would save her (48 - 32) = $ 16 per month
Answer:
here u go
Step-by-step explanation:
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